Field of the Invention
The present invention relates to an electroconductive film, and a touch panel sensor.
Background Art
Nowadays, as an input means a touch panel device has been widely used. A touch panel device includes a touch panel sensor, a control circuit for detecting a contact position on the touch panel sensor, a wiring, and a FPC (flexible printed circuit). A touch panel device is often used as an input means together with a display device in various apparatus (e.g. a ticket-vending machine, an automated teller machine, a cell phone, and a video game console) incorporated with a display device, such as a liquid crystal display and a plasma display. In such a device, a touch panel sensor is placed on a display screen of a display device, to thereby enable extremely direct input into the display device.
Touch panel devices are classified into various types based on the principle for detecting a contact position (approach position) on a touch panel sensor. A capacitance type touch panel device has drawn attention recently for reasons that it is optically bright, favorable in design, simply structured, superior in functions, etc. Although there are a surface type and a projection type in the capacitance type, a projection type is spotlighted, because it is suitable for addressing multi-touch recognition (multipoint recognition).
An example of an electroconductive film to be used in a touch panel of the projection-type capacitance-type includes a base material film and a transparent electroconductive layer formed on the base material film (e.g. refer to Japanese Unexamined Patent Application Publication No. 2011-98563). A transparent electroconductive layer is patterned, and functions as a sensor electrode of a touch panel.